Water is a critical resource in the recycling of plastic collected from households. Washing operations remove residues, dirt, and contaminants from plastic materials, preparing them for further processing and converting them into a reusable raw material. Because water is directly involved in the production cycle, accurately tracking water use is essential for detecting unusual conditions early and taking corrective action before they lead to excessive consumption or unplanned plant shutdowns. This was the challenge addressed by a project at a plastic recycling facility, where ISOIL Industria’s ISOMAG instrumentation was installed to provide reliable water flow measurement across multiple production lines.
Water use throughout the plastic recycling process
In mechanical plastic recycling, water is used throughout several consecutive processing steps.
Once the collected plastic has been shredded into flakes, the material typically undergoes multiple washing operations. One of the first is friction washing, where the flakes are cleaned through mechanical friction against one another and against the paddles inside the washing equipment. Detergents may also be added to remove oily residues and surface contamination. The material then passes through one or more rinsing stages to remove remaining detergent and contaminants.
Flotation is another important step. Plastic flakes are immersed in water tanks, where differences in polymer density allow different materials to be separated based on their floating behavior. This separation step is particularly important because it has a direct impact on the purity and quality of the recycled material.
With several processing stages often distributed across parallel production lines, measuring total plant water consumption alone does not provide enough information to understand what is happening within the process. A change in flow at a specific stage or production line may have several possible causes. Monitoring flow at individual points provides the detailed data needed to identify deviations and trace them back to their source.
Water measurement is also important during the treatment and reuse of washing water. Wastewater generated during the washing process is commonly treated through coagulation, flocculation, and sludge separation. Some facilities also use dissolved air flotation (DAF) systems. The treated water can then be returned to the production process instead of being discharged.
Accurate measurement of the water supplied to each line provides the information needed to determine how much water can potentially be recovered and reused. Over time, these measurements can also support the development of a plant-wide water balance based on actual operating data rather than estimates.
This was the operating environment in which the project described below was developed: multiple production lines, several water-intensive process stages, and distributed flow measurement requirements.
The Application
The facility included three washing lines and two additional lines dedicated to water supply, with flow measurement required at several points throughout the process.
The project had two main objectives: to accurately determine the water consumption of each line and to detect deviations from normal operating conditions as quickly as possible.
The Measurement Challenge
The customer needed a flow measurement solution capable of delivering accurate, dependable data, while also being straightforward to install and integrate into an existing operating facility.
The existing piping presented an additional challenge. Because the process lines were made of PVC, the selected flow measurement technology had to be compatible with the existing piping configuration without requiring extensive modifications.
The ISOMAG electromagnetic flow meters met these requirements by combining measurement accuracy and long-term reliability with straightforward installation and operation. The solution was also economically suitable for an application requiring a large number of measurement points.
The Solution: ISOMAG MS2500 flow meters with MV800
To provide the required measurement coverage, 48 ISOMAG MS2500 electromagnetic flow meters were installed at key measurement points throughout the facility, together with ISOMAG MV800 ultra-compact converters.
The instrumentation provides continuous data on water flow and consumption, giving plant operators a clear, real-time view of the operating conditions of each production line.
A major advantage of the installation was the ability to mount the instrumentation directly on the existing PVC piping without grounding rings. This simplified the installation considerably and made it possible to integrate the flow meters without extensive piping modifications or lengthy production interruptions.
Results and Key Benefits
The installation established a water monitoring system based on reliable, continuously available data. By measuring the amount of water used by each production line, operators can move beyond estimates and overall consumption figures and instead manage water use using detailed, verifiable measurements.
The main benefits include:
- accurate and reliable water flow measurement;
- real-time monitoring of consumption on individual production lines;
- faster identification of unusual water use;
- simplified installation on existing PVC piping without grounding rings;
- easy operation and a cost-effective solution for distributed measurement points;
- local technical assistance and support.
To learn more about ISOIL Industria’s range of ISOMAG electromagnetic flow meters or to request a free consultation, contact our specialists.
FAQ: ISOMAG flow meters for plastic recycling applications
Why is water essential to plastic recycling?
Washing, rinsing, and flotation use water to remove impurities and contaminants from plastic flakes and to separate different polymers according to density. These operations are essential for achieving the level of material purity required for the recycled plastic to be used again in manufacturing processes.
Can a flow meter be installed on PVC piping without modifying the existing system?
Yes. Some flow measurement technologies can be installed directly on existing piping, including PVC, without grounding rings or extensive modifications to the system. This can be especially valuable in operating facilities, where significant piping changes or extended shutdowns can increase project costs and disrupt production.
Why monitor water consumption in real time?
Real-time monitoring provides operators with detailed data instead of relying solely on estimates or total facility consumption. This makes it possible to recognize unusual water use quickly and take corrective action before it develops into unnecessary consumption or an unplanned shutdown.
What are the main advantages of the ISOIL Industria MS2500?
The MS2500 stands out for its high level of flexibility. A single sensor can cover a broad range of pipe sizes, flow rates, pressures, and temperatures and can be configured with different materials and converter options. This makes it a versatile choice when a configurable, flanged electromagnetic flow meter for industrial and water applications is required.
What are the advantages of combining the MS2500 with the MV800?
The strength of the solution lies in the complementary features of the two components. The MS2500 is a highly versatile sensor available in a wide range of sizes and configurations, while the MV800 provides a compact, protected converter that is particularly well suited to field installations.
